Foundations Sampler 2024

41 Lesson Plans 19 ©MathTeachersPress, Inc. Reproduction by anymeans is strictly prohibited. 19 Adding Unlike Fractions Lisa has completed _____of her weekly practice time. Add. 1 3 1 2 1 5 2 3 1 5 3 4 1 8 1 2 1 9 2 3 1 5 1 2 2 3 1 4 3 10 2 5 1. + 2. + 3. + 4. + 5. + 6. + 7. + 8. + Lisa did 1 4 of her weekly piano practice on Monday.She did 1 6 of her practice onTuesday.How much of her weekly practice time has she completed? 1 4 + 1 6 = 1 4 1 6 + = = 3 12 2 12 + The least commonmultiple of4 and6 is 12. What if the denominators are different and you need to add two fractions? Write a least three statements to explain. 11. Jane ate 1 5 2 of a candy bar and Ray ate 3 8 of the same candy bar. Is this possible? Explain. ___________________________ ___________________________ 9. Julie rode her bike 2 5 of a mile to school in the morning.After school she rode 1 2 of a mile to her after school job.How far did she ride in all? ___________ 10. Mary bought 1 3 of a pound of caramel and 1 5 2 of a pound of chocolate creams. How many pounds of caramel and chocolate creams did Mary buy? ___________ 12. Jess ate 1 4 of a pizza.Jack ate 1 3 of the same pizza.Dennis ate 1 2 of the same pizza.Is this possible? Explain. ___________________________ ___________________________ 6 5 1 7 0 1 1 2 1 1 7 0 1 1 3 5 2 19 0 8 5 9 7 1 9 0 of a mi. 3 4 lb. Yes: Jane ate 2 10 4 of the candy and Ray ate 2 9 4 of the candy. No: together they atemore than onewhole pizza. 1 5 2 1 5 2 1 5 2 Objective: To add fractions with unlike denominators. Materials: Multiple strips (made from the Table of Multiples, Master 4), Fraction Bars ® Adding with Fraction Bars The following activities prepare students to discover and use the patterns or rules for finding the lowest common denominator and changing the fractions into equivalent fractions. Write on the board: You are making a pizza topping with 2 3 cup of white cheese and 1 4 cup of yellow cheese. How much cheese in all? Allow each small group time to discuss possible ways to solve the problem using a set of Fraction Bars ® . Have students explain their thinking. Guide students to discover the Golden Rule of Fractions: you cannot add or subtract fractions unless they are the same color. To add 2 ⁄ 3 (yellow) plus 1 ⁄ 4 (blue), the bars must be changed to a common color. What common color can we change 2 ⁄ 3 and 1 ⁄ 4 to? (orange) Find the equivalent fractions in orange. ( 2 ⁄ 3 = 8 ⁄ 12 and 1 ⁄ 4 = 3 ⁄ 12 ) Write on the board: 1 8 2 + 1 3 2 = 1 1 1 2 Addition with Multiple Strips Demonstrate the same problem with the Table of Multiples (Master 4). Cut the multiplication table into multiple strips. Use your multiple strips to find the lowest common denominator and equivalent fractions for each pair of fractions. To add 2 ⁄ 3 + 1 ⁄ 4 , place the 2 multiple strip over the 3 multiple strip and the 1 multiple strip over the 4 multiple strip. X 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 2 4 6 8 10 12 14 16 18 20 22 24 3 6 9 12 15 18 21 24 27 30 33 36 4 8 12 16 20 24 28 32 36 40 44 48 5 10 15 20 25 30 35 40 45 50 55 60 6 12 18 24 30 36 42 48 54 60 66 72 7 14 21 28 35 42 49 56 63 70 77 84 8 16 24 32 40 48 56 64 72 80 88 96 9 18 27 36 45 54 63 72 81 90 99 108 10 20 30 40 50 60 70 80 90 100 110120 11 22 33 44 55 66 77 88 99 110 121132 12 24 36 48 60 72 84 96 108 120 132144 1 2 3 4 5 6 7 8 9 10 11 12 What is the smallest common number in the bottom row of each fraction, the 3 and 4 rows? (12) What number is above the 12 in the 2 row? (8) 8 ⁄ 12 is another name for 2 ⁄ 3 . What number is above the 12 in the 1 row? (3) 3 ⁄ 12 is another name for 1 ⁄ 4 . Write on the board: 2 3 = 1 8 2 + 1 4 = + 1 3 2 1 1 1 2 Together, read the example at the top of the page. Have students use fraction bars for the first row and multiple strips for the second row. In problem 11, students may generate multiples of 12 and 8 to find the lowest common denominator of 24. Skill Builders 17-1 - 2 2 4 6 8 10 12 14 16 18 20 22 24 3 3 6 9 12 15 18 21 24 27 30 33 36 1 1 2 3 4 5 6 7 8 9 10 11 12 4 4 8 12 16 20 24 28 32 36 40 44 48 Decimal Place Value IM2 Lesson Plan Students develop understanding of decimals using base ten blocks and money. Sample of Scripting (Bold Type) the sa e color. To add 2 ⁄ 3 (yellow) plus 1 ⁄ 4 (blue), the bars must be changed to a common color. What common color can we change 2 ⁄ 3 and 1 ⁄ 4 to? (orange) Find the equivalent fractions in orange. ( 2 ⁄ 3 = 8 ⁄ 12 and 1 ⁄ 4 = 3 ⁄ 12 )